The present invention relates to a stopping device with a stopper switch formed of, in combination, a stopping member for stopping an object to be detected at a predetermined position through abutment with the object, and a switch or control signal generating device for outputting a signal immediately before the object is stopped.
Heretofore, it has been generally carried out that an object to be detected, such as a table on which a work or an article to be measured is mounted, is stopped at a predetermined position by abutting against a stopping member, such as a positioning bolt.
In the above case, it is required to confirm whether an object to be detected abuts against the stopping member, or to switch a movement of the object to a reverse direction. More specifically, FIG. 5 shows a conventional positioning bolt 51, wherein a front end 50 of an object B to be detected is moved in a right direction on the drawing, and immediately before the object B is stopped by abutting against a head of the positioning bolt 51 fixed to a base wall 52, a projection 53 integrally provided at the front end 50 of the object B actuates a limit switch 54 to thereby produce a control signal, such as ON or OFF signal.
In the above structure, the projection 53 for actuating the limit switch 54 has to be provided at the front end 50 of the object B to be detected. Also, it is required that an operating position of the switch is adjusted by moving an attaching position of the limit switch 54 so that the control signal is produced immediately before the front end 50 abuts against the positioning bolt 51. Namely, in addition to the bolt and switch, an adjustment of the switch is required.
In order to simplify the structure and adjustment, the present inventor invented a positioning bolt 61 as shown in FIG. 6, wherein a switch is housed in a space of a central area of the positioning bolt.
In the structure as shown in FIG. 6, a sliding shaft 62 having, at a forward end thereof, a contact 63 for contacting an object to be detected is disposed in a hole provided in a bolt so that the sliding shaft 62 can slidably move in the hole. In this structure, dust, chips, water, cutting oil and the like enter into the hole for the sliding shaft 62, or sometimes further enter into an inner switching portion, so that the positioning bolt does not work properly.
In U.S. Pat. No. 5,412,168, a tool setter for sensing contact with a tool bit has a contact portion with a housing, and a switch. However, the contact portion is not designed to support a large force nor to actuate the switch precisely.
Accordingly, one object of the invention is to provide a stopping device with a switch, wherein a sliding member of the stopping device is properly sealed to provide dustproof and waterproof device.
Another object of the invention is to provide a stopping device with a switch as stated above, wherein a stop position of the switch can be set easily even if the stopping device is exchanged.
A further object of the invention is to provide a stopping device with a switch as stated above, wherein the abutting force of the moving member is properly supported and is not directly transmitted to the switch or control signal generating device.
Further objects and advantages of the invention will be apparent from the following description of the invention.